Notice how they are not plugged into the wall and there is nothing plugged into them. What exactly is nuts and dangerous? The guy just hung them up on a bookcase to store them there.
Well, other than looking like a festering landfill that only a pig would live in, plus the inherent potential hazard of having a bunch of wires hanging around loosely, nothing I suppose.
The very first thing every single Korean said upon entering the various apartments I lived in during my 6 years there was, "Wow! It is so clean."
I ain't got time for people who live like pigs.